The Best iPhone 4S External Battery?

Ideal on long trips and for heavy users, the best i4S external battery devices can save you from being stranded in the land of the blank screen...

iPhone batteries are pretty good but there will be times when you need more juice to get through the day or for those long trips. I have been using a New Trent battery pack for years, with good results, but there are plenty of other devices that can deliver some extra power when you need it.

A battery case like the Mophie will double the time between recharges and, if you like the design and don't mind the extra bulk, it can be a perfect solution.

The big advantage of a case is that there is nothing extra to carry (or lose). There are also no wires to get tangled.

Case, battery pack or push on?

The disadvantage of a battery case is that- unlike a battery pack- you cannot charge other devices like an iPod or iPad.

There are also some small battery life extenders that locate in the universal dock without being too obtrusive. They are easy to carry for emergencies and can give you a few precious hours of extra phone time.

New Trent iFuel and iCruiser

New Trent battery technolgy is reliable and the power they pack into a small space is impressive.

The 5000 mAh (milli-ampere hours) ifuel, pictured right, is probably the most popular single external battery in the US. It carries roughly three times as much juice as the i4s internal battery and that is enough to power movie viewing for 25 hours straight.

If you want a huge power resource there is the iCruiser IMP1000 which delivers 11000mAh. That might be what you need for a week camping in the mountains!

Both devices work with most kinds of iPod and iPad as well as older iPhones. Many of the more popular non-Apple phones can get a charge too, including HTC, Samsung and Blackberry (check individual models to be sure).

If you invest in some special adapters, these batteries will power most game consoles too.

Battery Cases

uNu Case in Matte Black or White

The matte black case is one of the most practical around. It is a great fit and the soft finish is more or less scratch proof as well as offering good shock absorbtion.

It has a 1700 mAh battery that, in theory, should recharge the i4s completely. In practice, it will give you at least 60% which means a very substantial increase in times between recharge.

Charging is via the standard Apple mini USB cable and both case and phone battery can be charged simulataneously- no need to remove anything.

The standard matte black case has recently been joined by a glossy white version. The looks will appeal to many people but bear in mind it is nowhere near as scratch proof and a lot more slippery than its cousin.